Part 2, 1913] DICRANACEAE 143 
suberect or subsectnd, often deciduous, from an oblong-lanceolate base gradually long-subulate, 
somewhat tubulose, the apex sparsely denticulate, the very narrow blade extending to near 
the apex; costa shortly excurrent, 300-400 » wide near the base and extending three fourths or 
more across the leaf-base, slightly ribbed on the back, in cross-section showing three layers of 
cells, the ventral large and empty, the median and dorsal layers small and thick-walled with 
stereid-cells intermixed; alar cells lax, thin, hyaline or fuscous, the cells next above them elon- 
gate-rectangular, about 12 » by 60 uw half way to the costa, those toward the margin narrower 
but not forming a distinct border, farther up irregular, becoming short, subrectangular to sub- 
rhomboidal, with somewhat thickened not pitted walls: fruit unknown. 
TYPE LOCALITY: Juan Vifias, Costa Rica, at 1130 meters. 
DISTRIBUTION: Known only from the type locality. 
This species is near C. tallulensis, but seems always to have a costa rather broader below, with 
the leaf-blade on either side narrower. 
20. Campylopus Hellerianus (Hampe) Jaeger, Ber. St. Gall. Nat. 
Ges. 1870-71: 417. 1872. 
Dicranum Hellerianum Hampe, Verh. Zool.-Bot. Ges. Wien 19:507, 1869. 
Plants in rather loosely cohering, greenish-brown tufts, with strict, scarcely branching 
stems tomentose below and up to 7 cm. high: leaves up to 6 mm. long by 0.8 mm. wide, uni- 
formly placed along the stems, erect when dry, slightly spreading when moist, lanceolate- 
pointed from a base with mostly parallel margins extending about one fourth up the leaf, the 
margins above incurved and entire to near the denticulate apex; costa percurrent or slightly 
excurrent, about three fourths the width of the lower part of the leaf, with smooth ribs less 
than one cell high on the back, in cross-section near the middle showing large ventral cells 
extending about one half through the costa and a stereid-band on the dorsal side with differ- 
entiated cells on either side of the band; alar cells more or less reddish, inflated, forming rather 
small or indistinct auricles; cells of the lower part of the blade pale, rectangular, with thin 
walls, the marginal ones gradually narrower, not forming a distinct border, upward becoming 
more or less rhomboidal with slightly thickened walls, those in the very narrow upper part of 
the blade small, short and obscure: fruit unknown. 
TYPE LOCALITY: Huatuseo, Vera Cruz. 
DIstTRIBUTION: Known only from the type locality. 
21, Campylopus tallulensis Sull. & Lesq.; Sull. Ic. Muse. 27. 1864. 
Plants in compact tufts, yellowish to dark-green above, dark reddish-brown and radiculose 
below with more or less divided stems up to 4 cm. high: leaves up to 6 mm. long, uniformly 
placed along the stems, when moist slightly curved and somewhat spreading all around, lanceo- 
late above from an ovate or oblong base, tubulose near the middle and grooved above to the 
short, stout, more or less denticulate apex; costa mostly less than two thirds the width of the 
leaf near the base, 200-350 » wide just above the alar cells, ribbed and dentate on the back 
above, in cross-section a little below the middle showing a row of large, thin-walled cells on 
the ventral side extending one half through the costa, and a median row of much smaller cells, 
with a stereid-band on the dorsal side; alar cells from reddish brown to hyaline, the cells just 
above usually pale, lax, thin-walled, more or less rectangular, often 16-20 « wide by 25-60 » 
long toward the costa, gradually narrower toward the margin, upward becoming smaller and 
shorter, square to rhomboidal, about 10 by 12-16 » with thicker walls and in the very narrow 
blade of the upper part of the leaf mostly elongate-rhomboidal. 
TYPE LOCALITY: Tallula Falls, Georgia. 
Distrieution: Georgia and Alabama. 
ILLUSTRATION: Sull. Ic. Musc. fl. 17. 
Exsice.: Sull. & Lesq. Musci Bor. Am. 736; ed. 2. 93. 
The type specimens of this species have the apex of the leaf mostly in poor condition and do 
not well show the teeth on the back and margins. 
22. Campylopus Donnellii (Aust.) Lesq. & James, Man. 79. 1884. 
Dicranum Donnellii Aust. Bot. Gaz. 4: 150. 1879. 
Plants in loose, yellowish-green tufts; stems erect, simple, radiculose below, up to 2.5 
em. high: leaves rather loosely imbricate and appressed below, comose at the summit, the 
